Photographic gelatinous liquid compositions



United States Patent 3,501,304 PHOTOGRAPHIC GELATINOUS LIQUIDCOMPOSITIONS Kenichi Koda, Tokyo, Sadao Sugita, Hanno-shi, and ShojiKikuchi and Katsumi Nishimura, Tokyo, Japan, assignors to KonishirokuPhoto Industry Co., Ltd., Tokyo, Japan, a corporation of Japan NoDrawing. Filed Mar. 7, 1967, Ser. No. 621,131 Claims priority,application Japan, Mar. 17, 1966, 41/ 16,095 Int. Cl. G03c N02 US. CI.96-94 2 Claims ABSTRACT OF THE DISCLOSURE Photographic gelatinous liquidcompositions containing as an anti-foaming agent a compound of thegeneral formula wherein n is an integer of 3 or 4 and m is an integer ofnot less than 5.

This invention relates to a photographic gelatinous liquid composition,characterized by that said composition contains a compound of thegeneral formula wherein n is an integer of 3 or 4 and m is an integer ofnot less than 5. More particularly, this invention is concerned with useof a new defoaming and anti-foaming agent in a photographic gelatinousemulsion or solution. It is accordingly an object of the invention toprovide a substantially foam-free photographic gelatinous emulsion orsolution which enables us to prepare a light-sensitive photographicmaterial efficiently and economically.

In the preparation of light-sensitive silver halide photographicmaterials, handling of a gelatine-containing liquid composition(emulsion or solution) is a very common work. It is necessary to handlesuch composition, for example, in the step of preparing an aqueousgelatine solution, the step of adding a water-soluble halide and awater-soluble silver salt (silver nitrate) to the aqueous gelatinesolution and the step of coating the resulting emulsion onto a support.As is well known, the gelatinous emulsion or solution is very liable tocause foaming, which often raises serious problems in processoperations. For instance, the emulsion components are not dissolvedcompletely nor dispersed uniformly, due to the foams formed by saidphenomenon. Further, in forming a silver halide by adding a halide and asilver salt to an aqueous gelatine solution, a heterogeneous reactiontakes place in the vicinity of the liquid surface due to the foams, withthe result that coarse silver halide particles, so-called coarse grains,are formed, which Will be a cause for undesirable fogging. In addition,when an emulsion involving foams is coated onto a support, the resultinglayer inavoidably suffers from unevenness or comet, which aredetrimental to the photographic product.

Furthermore, the foaming phenomenon is a great obstacle when theincreased production of a light-sensitive photographic material isintended. For example, in case the rotation of a stirrer is sped up, thefoaming becomes so vigorous that the content to be stirred is overflowedice out of the vessel together with the foams. Further, the foams onceformed do not disappear in a short period, and therefore it is ditficultby visual inspection to confirm whether or not the emulsion components(e.g., gelatine, halide and silver nitrate) have been dissolved.Moreover, the apparatus employed is required to have a spacecorresponding to the anticipated amount of foams, and hence shoulduneconomically be made larger in scale.

In order to dismiss such a foaming phenomenon as mentioned above,various defoaming agents have been proposed. However, these defoamingagents are still unsatisfactory. For example, C -C alcohols are requiredto be used in large quantities because of their insufiicient defoamingactivity. Further, use of such alcohols in a photo-film plant is veryhazardous because the operations in said plant are effected chiefly inclosed room and these alcohols are vaporizable, Silicon oils areexcellent in defoaming effect but, in the coating step, they bring abouta so-called repelling phenomenon to lower the quality of the products.

We have found that a compound of the above-defined general formula isvery effective as a defoaming and antifoaming agent for use in aphotographic gelatinous liquid composition. In the photographic art,undesired foaming is inherent to a gelatino-containing emulsion orsolution which may be light-sensitive or not. Thus, the compounddisclosed as a defoaming and anti-foaming agent in this invention isuseful for any gelatine-containing liquid composition used in thephotographic art, for example, including photographic light-sensitivegelatino silver halide emulsions, direct positive light-sensitivegelatino silver halide emulsions (which contain fogged silver halidecrystals) and non-light-sensitive gelatine-containing emulsons orsolutions to be used for coating of subbing layer, intermediate layer,anchoring layer and other auxiliary layer. In the following description,our reference sometimes will be made with reference to the foaming of alight-sensitive gelatino silver halide photographic emulsion. However,it should be understood that such description is informative only andthe principle of the invention is applicable, with success, to anyphotographic liquid composition as far as it suffers from foaming due tothe action of gelatine.

The compounds of the aforesaid general formula are excellent not only indefoaming and anti-forming properties but also in surface activeproperties. Thus, they further serve as surface tension depressants forphotographic emulsions or solutions, without any adverse effect on thephotographic characteristics of the said photographic emulsions orsolutions. If a compound of the above general formula is incorporated inan aqueous solution containing a foaming surface active agent withundesired foaming property, not only the foaming action of the surfaceatcive agent is decreased but also foams once formed are destroyed.Therefore, when used in combination with saponin or sodiumisoamyldodecylsulfosuccinate, both of which are excellent inspreadability but have frequently brought about various drawbacks due totheir foamability, the compound of the above general formula inhibitsthe foaming without injuring the preferable characteristic of saidsubstance, i.e. spreadability, and remove the foams once formed.

A compound of the above-indicated general formula can be prepared, ingeneral, by condensing 2 mols of epichlorohydrin with one mol ofpolyalkylene glycol in the presence of an acidic catalyst (e.g. Lewisacid), epoxidizing the resultingpolyoxyalkylene-bis-(3-chloro-2-oxypropyl)-ether with an alkali and thenhydrolyzing said invention is found to be excellent in surfacetensiondepressing ability.

Elementary analysis percent H percent 0H percent Average mol. weightNumber Number No. of n of m Found Calcd. Found Calcd. Found Calcd. FoundCaled.

In accordance with the present invention, such compound as mentionedabove is used, either as such or in the form of a solution in water orin a water-soluble organic solvent, such as a lower alcohol, at anoptional stage or stages in the steps for the production oflightsensitive silver halide photographic materials. The amount of thecompound added is most preferably about 0.01-10 g. per liter of thephotographic emulsion or solution to which the compound is to be added,but the amount is more or less variable in some cases. The compound ispreferably added prior to the step at which the formation of foams isanticipated, but it is not objectionable that the compound is directlysprayed over a portion in which foams have been formed. For example, inthe case where an aqueous gelatine solution is to be prepared, thecompound may have previously been incorporated in a given amount ofwater into which gelatine is to be dissolved, or may be added whilegelatine is under stirring and dissolution.

When the compound is used for a light-sensitive gelatino silver halidephotographic emulsion, it may preferably be added either before, duringor after the ripening or may be added to a supernatant formed during theprecipitation of light-sensitive silver halide crystals. According tothis way, a light-sensitive gelatino silver halide photographic emulsioncan be made free from undesired foaming, without any injury of itsphotographic characteristics at all, with the result that it is possibleto produce a light-sensitive silver halide photographic materialexcellent in quality at an improved production efficiency.

In order to demonstrate the effectiveness of the compounds disclosedherein, our explanation will be given in connection with the followingtests:

(A) SURFACE TENSION TEST Surface tension (dyne/cm.)

Agent Temperaused ture (G.) 0. 001% 0. 01% 0. 1%

Compound (IV) 43. 4. 37. 7 33. 8 Control 25 53. 6 47. 5 41. 1

As shown in the above, the compound of the present (B) FOAMING TESTVolume of foams (m1) Agent used After 1.5 min. After 5 min.

Not added 32 27 1 0. 5 4 3 As is clear from the above table, thecompound of the present invention is markedly excellent in defoaming andanti-forming properties.

The following examples describe certain ways in which the principle ofthe invention has been applied, but are not to be construed as limitingits scope.

Example 1 Into a cylindrical vessel of 1 m. in diameter and 2 m. inheight, 10 kg. of photographic gelatine and 1000 l. of water (deionized)were charged and the gelatine was swelled. To the vessel, 200 g. of thecompound (II) was added, and the mixture was stirred at a speed of 300-r.p.rn. for 30 minutes while maintaining the temperature at 50 C. Theheight of foams formed on the emulsion was measured to obtain thefollowing result, which is shown in comparison with the case where thecompound (II) was not used.

Height of foams, cm. Incorporated with compound (II) 0.2 Notincorporated with compound (II) 5 The run in which the compound (II) wasused could be carried out little foams which disappeared within 1minute, whereas the control run suffered from marked foams which did notdisappear even after 5 minutes. In the latter case, it was diflicult tovisually confirm the dissolution of gelatine. In the former case, noincrease in foaming was observed even when the stirring speed waselevated to 500 rpm.

Example 2 At the stage after the addition of silver nitrate in thepreparation of an high-speed photographic negative emulsion, 2 ml. perml. of the emulsion of a 1% aqueous solution of the compound (IV) wasadded. The emulsion was then added with stirring with a knownprecipitant (naphthalene-sulfonic acid-formalin resin), thereby toeffect precipitation of light-sensitive silver halide crystals. Thefoaming state of the emulsion was observed to recognize no substantialformation of foams. During the course of the emulsion preparation,samples were occasionally withdrawn and were subjected to foaming testsin the same manner as in the test B, thereby to obtain the results asshown below.

6 Example 4 3 ml. of a 4% aqueous solution of sodiumisoamyldodecylsulfosuccinate (hereinafter referred to as S) and 6 m1. ofa 1% aqueous solution of the compound Amount of foams Amount of foamsAmount of foams after silver salt after first dispersion after finishingof addition (ml) of emulsion (ml) emulsion (ml) After After After AfterAfter After 1.5 min. 5 min. 1.5 min. 5 min. 1.5 min. 5 min.

Incorporated with compound (IV) 0 0 0 16 0 Not incorporated 21 7 26 1726 14 The run in which the compound (IV) was used was entirely safe fromfoaming during the preparation of the photographic emulsion. The foamingafter finishing of the emulsion was ascribable to the fact that a moreor less amount of the compound (V) was lost due to water washing.

Example 3 1.5 ml. of a 4% aqueous saponin solution and 4.5 ml. of a 1%aqueous solution of the compound (III) were added to 50 ml. of ahigh-speed negative photographic emulsion. As controls, another emulsionincorporated with only saponin and still another emulsion notincorporated with any of these were prepared.

These three emulsions were subjected to foaming tests in the same manneras in Example 2 to obtain the results as shown below.

Amount of foams (ml) Agent used After 1.5 min. After min.

Not incorporated 30 24. 5 Saponin 100 62 Saponin and compound (III)--- 44 These emulsions were coated, respectively, on a film base and thendried. The resulting light-sensitive photographic films were subjectedto sensitometry to obtain the following results:

Photowas marked in unevenness or comet. Practically no commercial value.

Little None.

Incorporated with only saponin D Incorporated with saponin and comdopound (III).

As is clear from the above, the present invention inhibits the foamingof emulsions without giving any adverse efiect to the photographiccharacteristics of the emulsions, and enables us to obtain photographicproducts with good quality.

Volume of foams (ml) After 5 min. After 10 min.

Incorporated with S and compound (VII 42. 0 35. 5 Incorporated with onlyS 72.6 68. 5

Subsequently, the emulsion incorporated with S and the compound (VII)was applied onto a baryta paper, and the resulting emulsion layer wasfurther coated with a protective emulsion containing 1 ml. of a 1%aqueous solution of the compound (VII) and 0.5 ml. of a 4% aqueoussolution of S. No repellency and unevenness were observed in wet-on-wetdouble coating. However, when a protective layer incorporated with onlyS is applied onto an emulsion layer incorporated with only S, repellencyand unevenness was observed.

What we claim is:

1.A photographic gelatinous coating composition, which contains as ananti-foaming agent, a compound of the general formula wherein n is aninteger of 3 or 4 and m is an integer of not less than 5.

2. A photographic gelatinous coating composition as claimed in claim 1,wherein said composition is lightsensitive gelatino silver halidephotographic emulsion.

References Cited UNITED STATES PATENTS 2,240,472 4/1941 Swan 96942,768,894 10/1956 Harriman 96-94 I. TRAVIS BROWN, Primary Examiner US.Cl. X.R. 106-125

